When it gets to the correct pressure set my the regulator, it doesn't quit. It bogs down and then the belt slips. The pressure in the tank stays at the set pressure, the pump just bogs down.

Has the pressure regulator gone bad?

Other thoughts?

Ken
2019 Mystery Bike; EM Escape? Harley Road King?
2014 Yamaha FZ-09 Adventure
2011 KTM 450 Xc-W Six Days (plated)
1972 Honda CL350 Scrambler (project)Die young as late as possible, remember who you were before the world told you how it should be. -- Barry Morris

Sounds like the pressure switch is failing and trying to release but won't break contact all of the way. I had mine fail in the closed position a few months ago and the compressor ran for a long time while I wasn't home. Fortunately, the blow off valve still worked and saved my tank.

It took a few other air fittings, but I replaced my switch with a quality Square D pressure switch.